The valley of Alamut is situated in the north – east of Qazvin province. The region is an enclave in the form of a U shape valley in the central Alborz chains and opening up to the fertile Qazvin plains. The mountains of Alamut were ideal for construction of castles. The natural heights contains a section of the defensive structure of the castles.
In 1090 A.D, Hassan Sabbah , the leader of Ismailites in Iran , chose the Alamut region , as his headquarter to campaign , preach and convert new followers. This proved to be a turning point for destiny of Alamut Valley. The result of over two centuries Ismailite stronghold, the region witnessed innumerous castles throughout, of which at least 20 “castles “dating back to this era have been identified.
The most magnificent castle in the Alamut Valley is the Alamut or the Hassan Sabbah castle, which is built on top of a high rock reaching 2163 m above sea level near the Gazor Khan Village .The rock is 200 m high, with its steep slope and deep and dangerous ravine, the rock is practically inaccessible and forms a part of the Fort’s structure. Covering an area of 20,000sq.m. Currently only ruins of the fort and some towers are apparent and it is only through archeological excavation the mains can be discovered.
During the7 seasons of excavation (2001- 2007) more than 5000 Sq.m were unearthed.
The discoveries include: main entrances, road networks, steps and stepsflanked, workshops, water reservoirs, depots, living quarters, significant main portal and mosque. With molded and carved delicated brick decoration, as well as broken pieces of turquoise glazed tiles, luster painted tiles, these findings speak of the magnificents architecture of the castle during the Ismailite. Excavations show that the castle has undergone at least four major alterations, first in the 11 century A.D (Hassan Sabbah period), and then during his seven successors ( until 13th century AD ) and before the attack of Hulaku Khan in 1257 AD during the reign of Roknoddin Khorshah , the last lord of Alamut, the Safavid era 16-17A.D; when castle was used as prison and exile for political opponents and was referred to as “oblivious castle” and finally during Qajar unfortunately ravaged for treasure hunting.